Protective sealing compositions in the form of molded rings or sheets for application around surgical fluid drainage openings are known. A common formulation for such compositions comprises a gelled mixture of karaya gum and glycerin. See, for example, U.S. Pat. Nos. 3,302,647 and 3,954,105. As described in the first-cited patent, where the drainage opening is a stoma, the karaya-glycerin sealing composition may be used in the form of a molded ring which is placed around the stoma between the gasket of the ostomy appliance and the body of the wearer. The purpose of the ring is to provide a protective seal, that is, it is desired to prevent the intestinal fluid or urine being discharged from the stoma from leaking around the ring so that all of the discharged fluid is collected in the bag or pouch of the ostomy appliance. The sealing ring also performs the function of protecting the skin area around the stoma from the irritating urine or intestinal fluid, which in the case of ileostomies may include gastric juices. As illustrated by the second of the above-cited patents, the karaya-glycerin composition may also be used in the form of a sheet or blanket. Such blankets may also be used around stoma openings, or as described in U.S. Pat. No. 3,954,105, they may be used around drainage openings associated with a wound or surgical incision.
Sealing compositions of the kind described preferably have an initial tackiness, usually referred to as "dry tack", so that they will provide an initial adhesive adherence to the skin around the drainage opening. It is particularly important that the compositions provide a high degree of adhesiveness while in contact with aqueous fluid. This is usually referred to as "wet tack". The hydrocolloid in the composition, such as karaya, absorbs water which causes the hydrocolloid to swell and to increase in tackiness. However, with continued exposure to the aqueous fluid, especially where the fluid is urine or an intestinal discharge containing gastric juices, the composition tends to break down, losing mechanical strength, and eventually becomes ineffective for its desired protective sealing function. In application, such sealing rings or blankets must be frequently replaced. It has been desired to increase the mechanical and/or adhesive endurance of such rings or blankets, but heretofore no satisfactory means has been provided for accomplishing this result.